The lift producing structures such as wings, winglets, horizontal tails, canards etc. (hereinafter referred to as “wings”) for an aircraft or any mobile platform, commonly have an airfoil shape which includes a rounded nose, a relatively thick forward cross section, a tapering section, and a relatively thin trailing edge cross section. Aircraft wings commonly include ailerons and/or flaps to modify airflow over the wing to change the aircraft attitude or to increase lift for take-off and landing procedures, respectively. Ailerons and flaps are typically a significant percentage (i.e., approximately 15% and 35%, respectively), of an aircraft wing chord (the forward to aft length of a wing), and limited in spanwise extent so are therefore not efficient for optimizing wing span load distributions during flight to maximize aircraft performance.
It is known that the area adjacent to the trailing edge can be modified to include fixed wedge-shape devices or fixed extended flaps to improve lift and reduce the coefficient of drag for the wing. These fixed devices commonly have a length of approximately 5% of the wing chord. The addition of these devices can increase fuel efficiency at normal operating speeds of the mobile platform. The use of these devices, however, results in increased drag when operating outside the normal operating speed, because the fixed angle that the device makes from the plane of the trailing edge of the wing is optimized for the normal cruise speed, and therefore provides a less than optimum angle for operation at other than normal cruise speeds.
One known solution to the fixed flap design is to interlock a set of rotatable ribs to define the chord of an aircraft wing. The plurality of ribs are each rotatable such that the overall geometry of the wing can be modified during flight. In operation, either the entire wing deflects or a portion of the wing having one or more ribs deflects. The disadvantage of this design is the tradeoff between the additional weight required for the additional mechanical devices to modify the wing shape with the increased efficiency of the wing.
It is therefore desirable to overcome the disadvantages and drawbacks of the known airfoil designs having fixed trailing edge geometries or multiple articulated wing sections.